Lisi, I like the idea of changing the display manager. I chose LXDE for sufficient functionality and light weight and because I have read the Gnome did not support remote desktop in jessie or stretch.
Do you have a suggestion for choices? Maybe it doesn't matter, I can always change. That would seem to mean: Start up a new dm, delete LXDE, install a new instance of LXDE OK, I logged into the user account with shell. Instead of installing another dm, I used apt-get to remove and then autoremove LXDE in the shell. After rebooting, I still could not graphically log in. Logging on as root, I added myself in two user accounts with sudo rights. Both of these can login graphically. So the simptoms are gone. But I don't knnow how setup remote desktop, as that is where I broke my logon.